Arc-time recorder



9 1945 s. OESTREICHER ET AL 9 3 ARC-TIME RECORDER Filed June 26, 1945 NV K N- NW} ENVENTGRS T J 06 6 mm",

' c. WWW-414m- BY ATTO RN EY Patented Jan; 2,1945,

' OFFICE ARC-TIME RECORDER Sol Oestreicher and Erwin C, Brekelbaum, Milwaukee. Wis., assignors to Hamischfeger Corporation, Milwaukee, Wis., a corporation of Wisconsin Application June 26, 1943, Serial No. 492,656

2 Claims.

In the operation of production facilities in which arc welding apparatus is employed, particularly where a multiplicity of welders is functioning simultaneously, excessive clerical work has been required to maintain reasonable records for computation of costs and for determination of the compensation to which the individual welder is entitled. Efforts to simplify this problem by adoption of piece work methods of compensation have failed because hasty and imperfect workmanship toward which such a system trends should be avoided in any case, and particularly so in an operation such as welding. On the other hand, compensation based purely on time devoted to the work does nothing to encourage the industrious operator, unless adjustments are made in the time rate of compensation of individual operators. In a large operation it is difflcult to do this with such impartiality that it will not defeat its own ends.

By means of this invention an automatic con tinuous record of actual time devoted to welding by each operator may be graphically made, or a totalization of the time devoted t c/welding by each operator may be made, or both may be made simultaneously. Such a graphic record permits of detailed time studies of variou operations with little or no clerical work devoted to accumulation of time study data, while the totalized time furnishes an entirely impartial measure of operator output upon which a true incentive system of compensation may be based. The operator further is encouraged to perform the work in a thorough and workmanlike manner, and he is not penalized by circumstances beyond his control, such as poor fits in the work which require extra welding.

In order that apparatusfor this purpose be entirely satisfactory, it should be simple and reliable, capable of ready installation on present equipment, and capable of being housed in its entirety in a location away from the work so that it will not be damaged, and so that the temptation for tampering is removed. Furthermore,

such apparatus should be capable of reliably recording all of each actual welding operation, and also capable of discriminating the same from casually or deliberately imposed loads which are not of welding character. It is the object of this invention to fulfill these requirements.

' In the accompanying drawing forming a part hereof, specific forms of circuit embodying this invention are set forth by way of illustration and not of limitation, and in the same Fig. 1 is a diagram showing one form of the circuit of this invention, and Fig. 2 is a diagram showing a variation in the circuit arrangement of this invention.

Referring now to Fig. l, a circuit in accordance with this invention is shown in relationship to a typical source of welding current designated by the numeral I. The source of Welding current may be either a conventional welding motor-generator for supplying direct current, or the usual transformer or the like for furnishing alternating welding current. From the source terminals 2,

conventional heavy welding leads 3, shown in fragmentary form only, extend to the work to be welded.

Also connected to the source terminals 2, are light leads 4 and 5 which extend from the source I to the recording and discriminating parts of the circuit, which may be located in a remote position with respect to the source and separately housed if desired.

The discriminating parts of the circuit, as shown in Fig. 1, are made up of a normally closed voltage responsive relay 6, which, for example, when energized by a voltage in excess of 50 to 55 volts moves to open a circuit between contacts I and 8, and which when the energizing voltage falls to 45 to 40 volts, moves to reclose the circuit between contacts I and 8. The coil of the relay 6 is connected by leads 8 and I0 respectively, to light leads 4 and 5. The relay 6 will hereinafter at times be referred to as the open circuit or noload cutout relay.

In addition to the relay 6, the discriminating parts of the circuit include a normally open voltage responsive relay l I, which, for example, when energized by a voltage in excess of 1'1 to 20 volts, moves to close a circuit between contacts l2 and I3, and which when the energizing voltage falls to below 10 to 12 volts, moves to open the circuit between contacts I2 and I3. The coil of the relay II is likewise connected by the leads 9 and III to the light leads 4 and 5, as shown. The relay II will hereinafter at times be referred to as the short circuit cutout.

The recording parts of the circuit comprise a synchronous motor-driven time-recorder or electric clock I4, and if desired a graphic recorder I5, connected in parallel by the leads I6 and II. The clock I4 and recorder I! are or well known conventional con truction and therefore, are not described in detail since such details form no part of this invention. It will be sufllcient for those skilled in the art to point out that the graphic recorder I5, is an instrument having a clock driven paper chart engaged by a scribing number, which moves a predetermined distance transversely of the direction of movement of the chart when energizing current is applied through the leads I6 and I1. Such instruments are common -ly provided with multiple scribing members through corresponding multiple terminal connections, but for simplicity only a single scribing number is indicated.

A suitable source of ordinary commercial, controlled-frequency alternating current is provided through leads I8 and I 9. Line lead I8 is connected by lead 20 to contact 8, while contact I is connected by lead 2| to contact I3. Contact I2 in turn is connected by lead 22 to lead I1.

Lead I6 is connected by lead 23 to power lead I9 forming the other side of the alternating current supply. In this way current is supplied to the recording parts of the circuit under the control of the discriminating parts of the circuit.

In operation, in a typical sequence, the circuit shown in Fig. l, responds first and before weld ing current is draw through leads 3 by opening of the normally closed no-load relay 6, and as long as this condition prevails no current may pass from leads I8 and I9 to the totalizer I4 or the recorder I5. At the same time the potential of the welding current source I is efiective to close the short circuit relay I I in preparation for the response required when welding current is drawn. As soon a the operator starts to weld, the potential of the source I dropssubstantially and relay 6, being properly adjusted therefor, drops its armature and bridges and closes contacts I and 8. As soon as this occurs the totalizer I4 starts to move and the scribing mechanism of recorder I moves to cause a displacement in the line 21 drawn thereby. This condition prevails as long as welding current is drawn, but if the arc is interrupted relay 6 opens under the increased no-load potential of the source I, thus stopping the movement of the totalizer I4 and returning the scriber of recorder I5 to its base line position.

In the event that the operator attempts to maintain the totalizer I4 and recorder I5 in operation without actually welding, simply by short circuiting the source I, draw a heavy current therethrough, then relay II comes into action. This results from the fact that relay I I is adjusted to drop its armature whenever the applied potential falls below that delivered by the source I at the largest possible rate of current consumption by an actual welding operation. In this way temptation to the operator to subject the equipment to an injurious condition for the sake of creating a fictitious record is removed.

In view of the fact that relays 6 and II are intended to be responsive to potential variations, they are wound for high resistance in the case where a direct current source I is employed, or for high impedance in case the source I be an alternating current source. By reason of this a relatively small current flows in the leads 4 and 5 and they may be made of comparatively assau ts small wire, even though they are of considerable length without materially influencing the response of the apparatus. In this way the discriminating and recording apparatus may be conveniently housed in a suitable location, remote from the area where the welding is carried on so that accidental damage and tampering may be minimized.

In Fig. 2, is shown another variation of the circult of this invention in which leads 4' and 5 lead from the terminals of a welding current source not shown, and in a manner similar to that shown in Fig. l. The leads I and 5 join with the coil of a normally closed, no-load relay 6' adjusted to be responsive only to voltares in excess of those prevailing under welding conditions. Also joined to lead 4 by lead H is one end of the coil of a normally closed short circuit relay II. The other end of the coil or relay II is joined by a lead 25 to one contact l of relay 6, and thence through the other contact I of said relay, when closed, by means of lead 26, to electrical connection with lead 5.

The short circuit relay II' is provided with contacts I2 and I3 which serve as the final stage of the discriminating part of the circuit to control a recording and totalizing circuit, which is a counterpart of that shown in Fig. 1. To this end, supply leads I8 and I9 furnishing ordinary commercial, controlled-frequency alternating current are provided. Supply lead I8 is con nected through lead 20' and contacts I3 and I2 of relay II, when closed, with lead 22 which joins electrically with lead I1; while supply lead I9 is joined directly through lead 23' with lead I6. Leads I6 and II are joined both to the time clock or totalizer I4, and to the recorder I5 in the manner and for the purposes explained in connection with the corresponding circuit elements shown in Fig. 1.

The form of the circuit of this invention shown in Fig. 2 has the advantage that the relay I I is never subjected to voltages in excess of a maximum welding voltage which is somewhat less than the no-load voltage output of the usual welding source. Because of this the problem oi design of the relay II is somewhat simplified as compared with the problem involved in the case of relay II shown in Fig. l. Th relay II of Fig. 1 must be capable of withstanding continuous application of a potential, say for example, of volts, and nevertheless still function to open at voltages of, say 12 to 20 volts. On the other hand, and under comparable conditions, the relay II is not called upon to withstand a steady voltage in excess of, say 55 volts.

By means of either of the circuits of Fig. 1 or 2, it is possible to obtain an impartial and accurate record of the performance of a welding operator, on the basis of which such things as incentive compensation may be computed, or time study analysis may be made. Depending. Of course, upon the nature of the information desired, either the totalized record or the graphic record may be dispensed with.

We claim:

1. In a time-totalizing apparatus adapted for totalizing intermittent time intervals during which voltage within a predetermined range is prevailing in an electric load circuit the combination comprising, a recording circuit adapted for connection with a source of controlled frequency alternating current, a synchronous motor-driven electric clock contained in said recording circuit and adapted to be driven when said recording circuit is-energized, a normally-open switch in said recording circuit for controlling recording circuit is energized, switch means in said recording circuit for controlling the energization thereof, a discriminating circuit adapted for connection with said load circuit for response to voltage variations therein, and electromagnetic actuating means contained in said discriminating circuit cooperatively associated with said switch means contained in said recording circuit and adapted to actuate said switch means to maintain said recording circuit energized only when voltage prevailing in said load circuit is maintained within a predetermined range.

2. In a time-totalizing apparatus adapted for totalizing intermittent time intervals during which voltage within a predetermined range is prevailing in an electric load circuit the combination comprising, a recording circuit adapted for connection with a source of controlled frequency alternating current, a synchronous motor-driven electric clock contained in said recording circuit and adapted to be driven when said the energization thereof, an electro-magnetic actuator adapted to close said normally-open switch only when voltage is applied thereto in excess of a predetermined minimum, a normallyclosed switch adapted to control admission of energizing current to said electro-magnetic actuator, a second electro-magnetic actuator adapted to open said normally-closed switch only when voltage is applied thereto in excess of a predetermined minimum greater than said first-named predetermined minimum, and discriminating circuit connections adapted for connecting said load circuit to said second-named electro-magnetic actautor and thru the normally-closed switch controlled thereby to said first-named electro-magnetic actuator.

SOL OESTREICHER. ERWIN C. BREKELBAUM. 

